Fire-proof ceiling



(No Model.)

0. G. GILMAN.

FIRE PROOF CEILING.

No. 337,829. Patented Mar. 16, 1886.

, To all whom it may concern:

- myself solely to the use of this material, as

UNITED STATES ATENT OFFICE.

CHARLES CARROLL GILMAN, OF ELDORA, IOWA.

FIRE-PROOF CEILING.

fiFECIFICATION forming part of Letters Patent No. 337,829, dated March 1886- Application filed August 14, 1885.

Be it known that I, CHARLES CARROLL GIL- MAN, a citizen of the United States, residing in Eldora, Hardin county, Iowa, have invented a new and useful Improvement in Fire-Proof Ceilings, of which the following is a specification.

The object of my invention is to prevent the cracking or breaking of plastering applied to fire-proof ceiling slabs or blocks secured to joists of buildings, and this object I accomplish by the construction hereinafter described and claimed.

In the accompanying drawings,formingpart of this specification, Figure l is a view in cross-section, taken on line as x of Fig. 2, of a construction of ceiling embodying my invention. Fig. 2 is a plan view of the ceiling, showing two forms of washers or retainingplates. Fig. 3 is a view of the preferred form. Fig. 4 is a plan view of the ceiling shown in Fig. 3.

In the construction of my improved ceiling I prefer to use porous terra-cotta, otherwise known as "terra-cottalumber. This material, as is well known, is a non -combustible material which more effectually resists the action of fire than brick, is to a very high degree a non-conductor of heat and cold, and also of sound, is easily wrought with edged tools, such as used by carpenters, and will receive and hold nails or spikes. I do not, however, limit ordinary terra cotta or other fireproof material may be employed.

Referringto the drawings, A represents the wooden joists to which the slabs or blocks B of terra-coita lumber are secured. The said joists are placed the usual distance apart from twelve to sixteen inchesand the slabs B of terracotta lumber are made of a size, in one dimension, determined thereby.

As shown in Figs. 1 and 2, the slabs or blocks B are separated from each other, (leaving a space, H,) and also from the nail or nails D, passing between them into the joist A a sufficient distance to allow for the maximum amount of movement of the joists and nails relatively to the said slabs. Each nailor screw passes through a metal washer or retainingplate, 0 or 0, having an enlarged opening to Serial No. 174,359. (No model.)

permit the maximum amount of movement of the nail therein, the heads D of said nails being, of course, of greater diameter than the holes in said washers, so that the said heads V may operate to hold the washers in place. The slabs or blocks of terra-cotta lumber rest on said washers or retaining-plates, being held up against thejoist by said plates and the securing-nails. As the lumber or wooden part of the structure shrinks in time more or less, or is moved or shifted from other causes, the nails held by the joists will shift their positions relatively to the washers and slabs, without imparting any movement to the latter, and therefore the plastering that may be thereon cannot crack or break away, since it is not subjected to any strain.

The retaining-plate may be of the form shown at O, or it may be formed with an extension, O as shown at O, which extension is folded over the head of the securing nail and prevents the application of plaster to the said head, the latter having in this case a movement between the two layers of the re tainingplate. The form of plate shown at 0 answers very well for all practical purposes; but that shown at O is to be preferred, as the nail has more freedom of movement, and its head is not obliged to release itself from or cut its path through the plaster, and thus possibly loosen a port-ion thereof.

Instead of separating the slabs or blocks from each other, as shown in Fig. 2, they may be placed near or close to each other, each slab having a notch or notches, I, out in its edge or edges, as shown in Fig. 4. When two such slabs, similarly notched or cut away, are laid close to each other, a space equal to that shown at H, Fig. 1, is provided, in the center of which the securing-nail can be driven and the retaining-plate applied, as before described. The construction shown in Figs. 3 and 4 is preferred, though somewhat more expensive.

The plastering P is applied to the slabs or blocks, and covers the washers and nail-heads D or extensions 0 as the case may be.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

l. The combination of thejoists with ceiling slabs or blocks of afire-proof material secured to said joists by headed nails or screws placed at a distance from said slabs or blocks,

and by washers or retaining-plates having enlarged openings, through which the shanks of said nails pass, substantially as described.

2. The combination of the joists with ceiling slabs or blocks of a fire-proof material carrying a'coat of plaster and secured to said joists by headed nails or screws placed at a distance from said slabs or blocks, and by Washers or retaining-plates having enlarged openings, through which the shanks of said nails pass, substantially as described.

3. The combination of thej oists with notched ceiling slabs or blocks of a fire-proof material laid close together and secured to said joists by headed nails or screws located in said notches at a distance from the edges of said blocks, and by washers or retaining plates CHARLES CARROLL GILMAN.

. Witnesses:

EDMUND R1012,

It. B. GALUSHA. 

